APPLICANT'S ABSTRACT: Despite well-founded societal concerns over use of illicit drugs by youth, alcohol use has persisted for decades as the number one adolescent substance abuse problem in the U.S. Further, research has shown that the earlier the onset of alcohol use, the more likely a person is to develop alcohol dependence later during the life course. Consequently, the need is clear for interventions that will arrest this process at the earliest point possible. Hence, interventions that mobilize a youth's social systems to help that young person deal with the problem, i.e., the family and peer systems, would make sense from a number of standpoints. The first objective of the research proposed here is to compare the effectiveness of two different modalities. One of these is a state-of-the-art family therapy approach, Transitional Family Therapy (TFT), which integrates nuclear family, here-and-now interventions, with multigenerational issues. The other is a standardized version of the established modality of Adolescent Group Therapy (AGT), which includes both psycoeducational and therapeutic components. Both approaches have been developed expressly to target adolescent alcohol problems. Participants will be 140 males and females, ages 13-17, with diagnoses of alcohol abuse or dependence. Following random assignment to conditions, treatment in either condition will take four months in addition to two months of aftercare (six months total). Outcomes will be compared at treatment termination, one year post-treatment, and two years post-treatment. The second objective is to establish a standard as to the outcomes that can be achieved with AGT for this population. Even though group therapy is probably the most widely used treatment modality for such problems, there presently appear to be no clinical trails defining its parameters and expectation with adolescent alcohol abusers.